The present invention relates to an actuation device for a switch, particularly of a hand-held machine tool, of the type wherein an actuation member is displaceable by hand in the direction of switching of the switch.
An actuation device of the foregoing type has been disclosed in DE-OS No. 30 23 691. This conventional device has various disadvantages. The actuation means of this known actuation device rests at the end of its switching-on path in the arresting or locking end position with the support of a restoring spring, and the action of the restoring spring is retained in that end position. The switch remains in the switching-on position unless at the end of actuation the locking connection between the actuation means and its guide, for example the housing of the machine tool, is released. Such actuation devices are not, however suitable for use with so-called Totmann switches, the actuation-means of which must be released when the switch can be put to the switching-off position. On the other hand, known Totmann switches are disadvantageous because during the entire switching-on process they must be held in the switching-on position against the action of the restoring spring. For a reliable restoring position, the force of the restoring spring must be so great that the actuation end with the actuation means locked becomes quickly exhausted. This can lead to a non-observed switching-off of the hand machine tool. The actuation end must be subject to resting interruptions which are not required under other operation loads. A further difficulty for a designer of switch actuating devices of hand machine tools resides in that for some types of such machine tools, the actuation means has been utilized which was released only from its switching-on position whereas for other types of the machine tools only the Totmann function has been required. These actuation devices have been therefore manufactured for various purposes and kept in storage. This makes manufacturing and storing of the actuation devices rather difficult.